Soybean (Glycine max (L.) Merr.) production in Manitoba has increased substantially over the last 20 years, raising questions about phosphorus (P) fertilization in this region. Between 2013 and 2015, a study was conducted across 28 sites in Manitoba to evaluate the effect of P fertilizer rate and placement on soybean plant stand and seed yield. Treatments were 22.5, 45, and 90 kg P2O5 ha−1 applied as monoammonium phosphate, seed-placed, side-banded or broadcast, plus an unfertilized control treatment. Plant stand reduction due to seed-placed fertilizer toxicity was observed at five of 28 site-years, typically at the rate of 90 kg P2O5 ha−1. Stand reduction was most frequent on medium- to coarse-textured soils, dry soils or when seeding equipment had low seedbed utilization. Seed yield was reduced at two site-years due to seed placing 90 kg P2O5 ha−1, which reduced plant stands below the recommended threshold of 247 000 plants ha−1. Phosphorus fertilization did not increase seed yield, regardless of P rate, P placement, or Olsen soil test P level, except for one site-year where 45 and 90 kg P2O5 ha−1 increased seed yield by 343 and 430 kg ha−1, respectively. The extremely infrequent response to P fertilizer in combination with the high rate of P removal indicates that soybeans can use soil P reservoirs that are less available to other crops. Nevertheless, soybean growers in Manitoba should consider strategies for applying supplemental P to soybean or other crops in their rotation to maintain P fertility in soil.
How to translate text using browser tools
27 January 2025
Soybean responds infrequently to phosphorus fertilization in Manitoba
Gustavo R. Bardella,
Kevin H.D. Tiessen,
Don Flaten,
Mario Tenuta,
Yvonne Lawley,
John Heard,
Francis Zvomuya
ACCESS THE FULL ARTICLE
It is not available for individual sale.
This article is only available to subscribers.
It is not available for individual sale.
It is not available for individual sale.
phosphorus
placement
rate
seed yield
soybean (Glycine max (L.) Merr.)